Want to Remember Everything You'll Ever Learn? Surrender to This Algorithm

Alternative Titles

• The Polish Recluse Who Cracked the Forgetting Curve
• Why the Best Moment to Study Is Just Before You Forget
• One Algorithm, Endless Recall, and a Life Rebuilt Around It
• Inside the Lonely Experiment to Remember Everything You Learn

Key Takeaways

• Piotr Wozniak, a Polish programmer, built SuperMemo on the premise that there is an exact optimal moment to review material — right when you're about to forget it. Practice earlier wastes effort; practice later forces relearning. Because this moment differs for every person and every fact, only an algorithm can schedule it, which is what SuperMemo does for each discrete item a user is trying to retain.
• The underlying science is Hermann Ebbinghaus's 1885 discovery of the forgetting curve and the spacing effect: recall drops exponentially over time but can be dramatically extended by correctly spaced reviews. Psychologist Frank Dempster in 1988 called the spacing effect one of the most remarkable findings in learning research and lamented the failure to apply it — educators never adopted it because determining the precise moment of forgetting is impossible without computation.
• Wozniak's early data, gathered on paper starting around 1982, showed the scale of the problem: 40 percent of his English vocabulary and 60 percent of his biology answers evaporated over time. Using naive methods, retaining a 15,000-word English vocabulary would have required two hours of daily practice, and 30,000 words four hours — impractical, which is why fluency usually demands immersion rather than classroom study.
• SuperMemo tracks each item's forgetting curve individually and reminds the user to rehearse when recall probability drops to roughly 90 percent. Each successful review flattens the curve, so intervals grow: five days, then weeks, then months, then years. Wozniak refined this over nearly a decade of self-experimentation, testing different interval schedules on thousands of his own flashcards before landing on an algorithm that also adjusts per-item difficulty.
• UCLA's Robert and Elizabeth Bjork developed a model that explains why SuperMemo works and why conventional study feels productive but isn't. Memory has two components: retrieval strength (how accessible a memory is now) and storage strength (how deeply rooted it is). Crucially, storage gains from practice are inversely correlated with current retrieval strength — the harder you have to work to recall something, the more it gets sealed in. Easy fluency during a lesson is therefore a misleading signal of real learning.
• This is why products like Rosetta Stone, which optimize for the user's sense of progress with constant feedback and clues, defy the lab findings. CTO Greg Keim cites Amazon reviews as evidence of effectiveness, but the subjective feeling of knowing is precisely what researchers say to distrust. Forgetting isn't decay either — Bjork notes memories remain stored but inaccessible, recoverable through recognition or a single reminder, which is why spaced reviews at the edge of forgetting are so powerful.
• Wozniak extended the algorithm beyond flashcards with 'incremental reading': he pastes articles and book excerpts into SuperMemo, assigns priorities, and the system feeds him snippets when he's ready to absorb them, converting unread material into scheduled, remembered knowledge. He reads until comprehension drops, then moves to the next queued item. He says books 'gradually evaporate' as they translate into durable knowledge.
• The cost is a life organized entirely around the algorithm. Wozniak refuses alarm clocks, sleeps when tired regardless of time of day, blocks his days into creative, reading, exercise, eating, and rest periods, owns no phone, ignores email for months, skips conferences, and disappears for extended retreats (two weeks in 1994, 100 days in 1995). He also calculates that a human lifetime permits only a few million learned items, so he guards his health — swimming in 40-degree Baltic water, avoiding car trips — as a way to expand his intellectual ceiling.
• Wozniak's own checklist for becoming a genius: clarify goals, use spaced repetition, preserve health, work steadily, minimize stress, refuse interruption, and never resist sleep. The author's conclusion is that the real barrier to mass adoption isn't the software's interface or the brain's capacity but human temperament — the spacing effect loses force after a few skipped days, and few people will subordinate social life to an algorithm. SuperMemo sold only about 50,000 copies in 2006, mostly under $30, suggesting the tool works but the discipline it demands is rare.

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